Rope or cable



(No Mod-GLN 0. lVI. THOMPSON. ROPE 0R CABLE.

N paens, Pham-ummm', walmngm n.0.

FFICE.

COLIN M. THOMPSON, OF BROOK IJYN, NEIV YORK.

ROPE OR CABLE.

SPECIFICATION forming part of Letters Patent N o. 400,970, dated April9, 1889.

Application filed February 10, 1885. Serial No. 155,505- (No model.)

To all whom it may concern:

Be it known that I, COLIN M. THOMPSON, aY

citizen of the United States, and a resident of the city of Brooklyn,county of Kings, and State of New York, have invented certain new anduseful Improvements in Ropes or Cables', of which the following is aspecification.

My invention relates to that class of ropes or cables which are designedfor use as wrapping conductors to connect pulleys on separate shafts fortransmitting power, and especially for use in connection with cablerailways; and it has for its object to so construct the cable as toenable the gripping devices to grasp the same more firmly, and also tosecure a better wearing-surface, more durable and less liable to becomebroken or frayed than th at `of cables made in the ordinary manner, andyet maintain the requisite flexibility of the rope without any undueincrease in its sectional area. I secure these objects by making acompound cable having a non-extensible flexible core, a wrapper ofrubber surrounding the core, and an outer portion of heavy wires orstrands, substantially as illustrated in the accompanying drawings, andas fully hereinafter described, and specilically pointed out in theclaims.

In the drawings, Figure l is a longitudinal view in part section,illust-rating my improved cable. Fig. 2 is a transverse sectional Viewon the line l 2, Fig. l; and Fig. 3 is a view representing a section ofa cable constructed according to my invention and held within the jawsof a gripping device, shown in section, such as is used on street-cars,duc.

Wire cables intended for the transmission of power, cable railways, oras wrapping conductors for use to connect pulleys in mills or forraising elevators, dro., have heretofore been generally made by twistingtogether strands of nearly the same size, the outer portions of suchcables in the majority of cases consistin g of comparatively smallwires, which are rapidly worn away by the frictional contact of thegripping devices, pulleys, &c., so that the rope in a short time becomesfrayed and is apt to get entangled with the gripping devices or slipfrom the pulleys.

lVhile the use of heavier wires upon the eX- terior face of the ropewill render it more durable and obviate the objections above referredto, the application of the same directly to an incompressible center orbody of the cable results in making the whole so stiff and rigid that itwill not readily bend around pulleys of ordinary diameter without beinggreatly strained and soon broken.

I have succeeded in constructing a cable not open to any of theobjections specified, and which permits a much firmer grip than can besecured upon cables of the ordinary construction, as well as to be bentabout a smaller pulley. f

I provide the cable with a central non-eX- tensible portion or core, b,which may, if desired, consist of an ordinary wire cable composed ofcomparatively small wires laid parallel with each other or twisted intoa rope in the ordinary manner. In practice, however, I prefer to makesaid core b of a flexible slightlyelastic material, as rope .or hemp,with surrounding layers of wire, as shown in Figs. l and 2. I surroundthe core b with rubber a to the desired depth, which I again surround orinclose in an external wrapper, B, of large wire, winding the samespirally around the rubber a, as shown in Fig. l.

Vhile the wires composing the external portion, B, of the cable may beof sufficient thickness to insure the requisite durability ofsaid cableand prevent the same from becoming frayed or broken by any ordinaryamount of wear, they yet will not impart undue stiffness or rigidity tothe cable, because of the underlying bodies of resilient andslightly-elastic material-viz., the rubber wrapper a andslightly-elastic coreh-which permit the outer wires to change theirposition to a slight extent when the cable is bent around the peripheryof a pulley, thereby permitting such bending to be readily effectedwithout strain upon the outer wires, and thus securing the desiredflexibility-functions that cannot be fulfilled by a cable wherein heavyouter wires lie in direct contact with a body of rigid elastic orresilient material.

The principal advantages resulting from combining the outer portion orwrapper and inner portion or core with an intervening layer of rubberlie in the capacity of the cable to Ol IlOIl A IOO bend or pass aboutsmall pulleys, as well as beeoine slightly eonlpressed between the jawsy aetion is illustrated in a somewhat exaggerated form in Fig. Lin whiehthe dotted lines represent a Gable, and e relnfesentthe opposi te ljawsot' a grip, G, pendent in the usual manner l`ro1n a street-ear. As thejaws b e are brought together the elastie resilient portion u, willyield to a eertain extent', so that when t-he cable is compressedbetween the jaws, and thereby slightly reduced in diameter, shoulders a:.fr will be formed outside oi' and against the edges ot the jaws, whichoperate to prevent the grip Afrom slipliinel upon the surface ol theCable and to insure a niueh firmer connection than would be praetieablein eases where .i'rietion ln'ztween the surlaees oll the jaws and thecable alone is depended upon.

lVllile the cable above described possesses the requisite llexibilityand durability, the use ol' the heavy outer wires does not necessitateany undue increase in diameter, so that the improved eablellas nogreater eross-seetional area than one of the same strength made in theordinary manner.Y

From the foregoing rleseriptiou it will be observed that my improvedeable is espeeially adapted for use with cable railways, and can also beadvantageously employed for any purposes reqliirin its use in eonneetionwith pul leys, espeeial ly where it is desirable that the Cable beflexible as possible, in order to readily pass about the peripheriesoli' pulleys oi' eonlparatively small diameter.

l. A cable consisting' ot a non-extensible slightly-elastic and flexibleeore7 au'rappcn-oi' rubber surrounding' said oore7 and an externalwrapper' oli' large wire spiral] y arranged about. said resilientwrapper, substantially as described.

2. A cable Composed ot a eore formed ol:` hemp or other slightly-elasticmaterial inelosed by small wire, a wrapper of rubber surrounding saidCore, and an external rapper inelosingl said rubber wrapper, saidexternal wrapper formed otl large wire Ispirally arranged with regardtothe longitudinal axis oli' the cable, as and for the purposespecified.

In testimony whereof I have signed my naine to this specification in theVpresenee ot' two subseribing witnesses.

lVitnesses:

il. R. l-ZALnwiN, L. En (lorninmn.

